Follow-up study in local allergic rhinitis shows a consistent entity not evolving to systemic allergic rhinitis

Background: Local allergic rhinitis (LAR) is a common disease that affects 25.7% of the rhinitis population and more than 47% of patients previously diagnosed with nonallergic rhinitis. Whether LAR is the first step in the natural history of allergic rhinitis (AR) with systemic atopy or a consistent entity is unknown. Objective: The aim was to evaluate the natural history of a population with LAR of recent onset and the development of AR and asthma. Methods: A prospective 10-year follow-up study with initial cohorts of 194 patients with LAR of recent onset and 130 healthy controls is being undertaken. A clinical-demographic questionnaire, spirometry, skin prick test, and specific IgE to aeroallergens were done yearly. Nasal allergen provocation tests with Dermatophagoides pteronyssinus, Alternaria alternata, Olea europea, and a mix of grass pollen were performed at baseline and after 5 years. Results: At disease onset, most of the patients with LAR had moderate-to-severe persistent-perennial rhinitis; conjunctivitis and asthma were the main comorbidities (51.1% and 18.8%, respectively), and D pteronyssinus was the most relevant aeroallergen (51.1%). After 5 years of follow-up, a worsening of rhinitis was detected in 26.2%, with an increase in symptom persistence and severity, and new associations with conjunctivitis and asthma. Atopy was detected by skin prick test and/or serum specific-IgE in patients with LAR (6.81%) and in controls (4.5%). Conclusions: This study shows a similar rate of development of systemic atopy in LAR and controls, which suggests that LAR is an entity well differentiated from AR. To determine the natural course of LAR more precisely, this study is in progress to complete 10 years of follow-up.